The invention relates to a fuel injection system for a multi-cylinder Diesel internal combustion engine with separate common fuel supply lines for at least two groups of cylinders from which high-pressure fuel is supplied to the injectors of the cylinders in a group.
A fuel injection system is known, for example, from EP 05 01 459 A2, in which a mechanically driven high-pressure pump delivers fuel into a common supply conduit (common rail) from which individual injection conduits lead to magnetic valve-controlled injection nozzles.
DOS 42 33 273 A1 discloses a fuel injection system with two high-pressure fuel supply conduits for different groups of cylinders with provisions for returning the leakage fuel to the pump rather than the fuel tank in order to decrease the fuel pumping requirements.
In the case of a defect of an injection nozzle due to leakage or in the case of a fault in a magnetic valve which keeps such valve open, the supply conduit pressure necessary for satisfactory fuel injection falls so that satisfactory operation of the internal combustion engine is no longer warranted; in fact, the internal combustion engine may be destroyed in such an event.
The object of the invention is, therefore, to provide measures by which safe emergency operation of the multi-cylinder internal combustion engine can still be maintained when such a fault occurs.